Millard
method of making sealing members



Dec. 23', 1969 P. v. MILLARD METHOD OF MAKING SEALING MEMBERS 4Sheets-Sheet 1 Original Filed Jan. 5, 1961 mmvron. Pu/u/P I/. M14 4 A00AffORA/EYS Dec. 23, 1-969 P. V. MILLARD 4 METHOD OF MAKING SEALINGMEMBERS 4 Sheets-Sheet 2 Original Filed Jan. 5, 1961 INVEN TOR.

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fill/4 /P n M144 4R0 BY A TI'OR/VA'YS Dec. 23, 1969 P. v. MILLARD METHODOF MAKING SEALING MEMBERS Original Filed Jan. 5. 1961 .4 Sheets-Sheet 4United States Patent Oflice Re. 26,740 Reissucd Dec. 23, 1969 26,740METHOD OF MAKING SEALING MEMBERS Phillip V. Millard, Lighthouse Point,Fla., assignor to Automotive Rubber Company, Inc., Detroit, Mich., acorporation of Michigan Original No. 3,272,904, dated Sept. 13, 1966,Ser. No.

409,141, Nov. 5, 1964, which is a division of applications Ser. No.80,444, Jan. 3, 1961, and Ser. No. 163,411, Jan. 2, 1962. Applicationfor reissue Oct. 29, 1968, Ser. No. 777,542

Int. Cl. B29h 9/10 U.S. Cl. 264-274 6 Claims Matter enclosed in heavybrackets appears in the original patent but forms no part of thisreissue specification; matter printed in italics indicates the additionsmade by reissue.

ABSTRACT OF THE DISCLOSURE A method of making a sealing member in whicha sheet metal body is formed with a peripheral flange and is supportedon an open mold with the flange suspended in a cavity of the mold.Uncured vinyl plastic material is poured into the mold cavity and isthen cared to provide a resilient seating edge accurately located withrespect to the metal body.

This application is a division of my co-pending applications, Serial No.80,444, filed January 3, 1961, now Patent No. 3,182,119 and Serial No.163,411, filed January 2, 1962 and now abandoned.

This invention relates to scaling members such as insulating grommetswhich are used to insulate wires, cables and pipes from a panel throughwhich they are threaded, 1

gaskets such as annular resilient sealing gaskets having accuratelyformed surfaces and sealing members comprising rigid bodies havingresilient sealing gaskets along a peripheral edge thereof.

In various automotive and aeronautical applications, it is necessary tothread wires, cables or pipes through an opening in a wall or panel. Itis desirable and often necessary that these items be insulatedelectrically from the panel. In addition, because of the great emphasisbeing placed on sound proofing and moisture proofing, it is desirablethat the arrangement be such that sound and moisture will not betransmitted by movement of the wires, cables or pipes relative to thepanel. Heretofore, grommets have been made by dipping or pressuremolding the resilient materials comprising the grommets about a clip orthe like.

It is therefore an object of this invention to provide a novel methodfor forming grommets of the above-mentioncd type.

The novel method for forming the grommets comprises positioning the ringin an open mold with the prongs extending upwardly, the outer edge ofthe ring engaging projections or a shoulder in the side wall of the moldthereby holding the ring in spaced relation to the bottom of the mold. Apredetermined quantity of an uncured elastomeric composition in liquidform is poured into the mold and the elastomer is cured. When theresultant grommet is removed from the mold, it has been accuratelyformed and the ring is embedded in the interior thereof with the prongsextending outwardly. A preferred type of elastomeric compositioncomprises what are commonly known as plastisols. Closed cell foamedplastisols are especially suitable for grommets embodying the invention.

At the present time, conventional resilient gaskets are made either bycutting the gasket from a sheet of resilient till material or bypressure molding the gasket in a closed mold. However, making thegaskets by cutting is an expensive operation due to the great waste.Also, making the gaskets by pressure molding is also expensive due tothe cost of the molding equipment.

It is therefore an object of this invention to provide a method forforming an annular gasket which is generally rectangular in crosssection and has accurately formed bottom and side surfaces and may haveaccurately formed holes and projections.

It is a further object of the invention to provide a method for making asealing member formed of a metal body and an edge portion formed ofresilient material which also has accurately formed bottom and sidesurfaces.

The invention contemplates the formation of gaskets by pouring apredetermined quantity of uncured vinyl plastic material in an open facemold having a cavity in one surface thereof which has accurately formedsurfaces. Accurately formed and located pins may be provided in thecavity to form accurately formed and located openings in the gasket-Similarly, the cavity may be provided with accurately formed projectionsto define desired projections on the gasket. Where the gasket is to beformed on the sheet metal body of a sealing member, the mold is providedwith locating means that accurately locate the sheet metal member insuch a fash ion that the sealing edge is suspended in the cavity so thatthe uncured vinyl plastic material surrounds the edge of the sealingmember and forms a gasket on the edge when the uncured vinyl plasticmaterial is cured.

Referring to the drawings:

FIG. 1 is a fragmentary perspective view of a grommet embodying theinvention shown in position in an opening in a vertical panel.

FIG. 2 is a fragmentary sectional view taken along the line 2-2 in FIG.1.

FIG. 3 is a bottom view of a ring which forms part of the grommetembodying the invention.

FIG. 4 is a bottom view of the grommet shown in FIGS. 1 and 2 embodyingthe invention.

FIG. 5 is a fragmentary sectional view showing the apparatus for formingthe grommet of FIGS. 1 to 4.

FIG. 6 is a view similar to FIG. 5 showing the grommet after it has beenformed.

FIG. 7 is a sectional view similar to FIG. 2 of a modified form ofgrommet.

FIG. 8 is a sectional view similar to FIG. 6 showing the apparatus formaking the grommet shown in FIG. 7.

FIG. 9 is a plan view of a still further modified form of grommet.

FIG. 10 is a fragmentary sectional view of an apparatus for making thegrommet shown in FIG. 9.

FIG. 11 is a plan view of a further modified form of grommet.

FIG. 12 is a sectional view taken along the line 1212 in FIG. 11.

FIG. 13 is a fragmentary sectional view of the apparatus for forming thegrommet of FIGS. 11 and 12.

FIG. 14 is a perspective view of a further modified form of grommet.

FIG. 15 is a plan view of a mold used in making the gasket embodying theinvention.

FIG. 16 is a sectional view on an enlarged scale taken on the line 1616in FIG. 15.

FIG. 17 is a sectional view on an enlarged scale taken on the line17--17 of FIG. 15.

FIG. 18 is a sectional view taken on the line 1818 in FIG. 15.

FIG. 19 is a view showing various cross sections of gaskets that can bemade in accordance with the invention.

FIG. is a sectional view taken on the line 20-20 in FIG. 15.

FIG. 21 is a plan view of a modified form of mold.

FIG. 22 is a plan view of a sealing member embodying the invention.

FIG. 23 is a plan view of a mold for making the sealing member shown inFIG. 22.

FIG. 24 is a fragmentary sectional view on an enlarged scale taken onthe line 2424 in FIG. 23.

FIG. 25 is a perspective view of a modified form of sealing member.

FIG. 26 is a plan view of an apparatus for making the sealing membershown in FIG. 25.

FIG. 27 is a fragmentary sectional view on an enlarged scale taken alongthe line 2727 in FIG. 26

Referring to FIG. 1, grommet 20 embodying the invention is adapted to bemounted in an opening 21 of a vertical panel 22. As further shown inFIG. 2, the grommet 20 comprises a generally cylindrical body 23 of softresilient material such as foamed rubber, foamed plastic or soft denseplastic. Boy 23 is of general uniform axial thickness and a ring 24 isembedded in the body 23. Body 23 thus includes a flat annular surface 25which is adapted to engage the edge of the opening 21. As shown in thedrawings, ring 24 is positioned axially relative to the body 23 near thesurface of the body 23 which is remote from surface 25 andincludescircumferentially spaced integral fingers 26, 26a shaped in theform of spring members that are adapted to engagethe sides of theopening 21 to hold the grommet in position, compressing the body 23 sothat the surface 25 engages the edge of the opening 21. Finger 26aextendsoutwardly engaging the edge of opening 21. As shownnn FIG. 2,each finger 26 includes an outwardly extending portion 27 and thegrommet is applied by forcing the. fingers axially through the opening,momentarily bending the fingers 26 inwardly so that after they passthrough the opening they return to their original position drawing thering 24 and, in turn, the body 23 axially toward the opening 21 andcompressing the portion 25 of the body 23 which contacts the edge of theopening against the opening. The compression and the softness of thematerial 15 such that the material is partially deformed into theopening 21.

The grommet 20 is preferably made by foaming or casting the softresilient material in place about the ring 24. An apparatus for makingthe grommet is shown in FIG. 5 and comprises a mold 30 which includes anopening 31 having a peripheral shoulder or ledge 32 against which theperiphery of the ring 24 rests thereby holding the ring in spacedrelationship to the bottom of the opening 31. An insert 32 in mold 31provides the opening 33 through which the cable C extends. The ring 24is placed in position with the fingers 26 extending upwardly and thefoamed plastic is poured into the mold to fill the mold as shown in FIG.6. The plastic is then cured in an oven or at room temperature, if it isof the room temperature curing type, and the grommet is removed from themold.

A modified form of grommet is shown in FIG. 7 wherein the body 35 has anose or axially extending portion 36 surrounding the opening 37 throughwhich the wire, cable or pipe extends. This form of the invention isparticularly useful for use with pipe, rods and the like, which mayextend at an angle to the opening through the panel. The nose 36 engagesthe pipe and provides a good seal between the pipe and the nose.

The grommet shown in FIG. 7 may be formed in an apparatus such as shownin FIG. 8 which includes a mold 40 having an opening 41 thereinincluding a frusto-conical portion 42. Opening 41 is formed with aperipheral ledge 43 on which the ring 24 is positioned. The moldincludes an upper section 44 that has an axially extending pin 45 thatis adapted to extend into the projection 42 to form the opening of thegrommet. In making the grommet,

the ring 24 is placed in the opening 41, the foaming plastic is pouredinto the opening and then the section 44 is brought into positionforcing the pin 45 downwardly into the projection so that when the foammaterial is cured the grommet is formed with an opening. After curing,the section 44 is removed and then the grommet can be removed from themold 40.

A further modified form of the invention is shown in FIG. 9 and FIG. 10wherein an addition to nose sections 50, the grommet includes areinforcing plate 51 that is placed in position over the ring 23 beforecasting the grommet. The plate 51 may comprise fiber board, metal or thelike and includes opening 52 aligned with the openings 53 of the noseportions 50. The disc or plate 51 operates to give rigidity to thecentral portion of the grommet.

A further modified form of the invention is shown in FIGS. 11 and 12wherein the grommet is formed with an integral circumferential sheet 61that is embedded in the grommet. The sheet is formed in such a mannerthat a bolt 62 can be threaded into the sheet extending through theopening of the body of the grommet thereby providing a mounting for somepiece of apparatus on the grommet. For example, a nut 63 can be threadedon the bolt 62.

The grommet shown in FIGS. 11 and 12 may be made in an apparatus such asshown in FIG. 13 which includes a mold 64 having an upper section 65with a downward- 1y extending pin 66 that extends into the opening insheet 61. The mold 64 is formed with a shoulder 67 that spaces the ring23 in the same manner as in the previous forms of the invention.

The form of the invention shown in FIG. 14 comprises a grommet 20a thatis identical to that shown in FIGS. 1, 2 and 6 except that the grommetis cut along a radial plane as at 20b so that the grommet can be placedover a wire or rod 70 that is already in position passing through thewall 22. The cut 20b can be made after the. grommet is formed by cuttingthrough the body 23 and the ring 24, or alternatively, the ring 24 canbe cut through prior to forming of the grommet and a battle (not shown)can be used in the molding process so that when the grommet is molded,the slit 20b is formed therein. The slit 20b can lie in a single planeor can be a sinous or corrugated configuration.

Referring to FIG. 15, in the practice of the invention, an open facemold is used having an annular cavity 121, the surfaces of which areaccurately formed to define the sides and bottom of a gasket. Apredetermined quantity of a vinyl plastic material is introduced intothe cavity 121 and the material is cured in situ to form the gasket.

As shown in FIGS. l6, l7 and 18, the cavity 121 includes accuratelyformed side surfaces 122 and bottom surface 123 so that the resultantgasket has a cross section which includes accurately formed sidesurfaces 124 and bottom surface 125. The top surface 126 of the gasketconstitutes the natural surface of the cured plastic and is notaccurately defined by any surface.

By modifying the molding, various openings and projections may beprovided on the finished gasket G. For example, as shown in FIGS. 15 and16, a pin 127 can be accurately located in the cavity 121. The surfaceof the pin 127 is accurately formed so that the plastic material whencured about the pin defines an opening that is accurately located andformed. As shown in FIGS. 15 and 17, a cutaway can be provided in thegasket by making the cavity narrower as by a projection 128 on the mold.As shown in FIGS. 15 and 18, a shallow depression or opening 129 can beprovided in the bottom surface of the gasket by locating a short pin orprojection 130 accurately in the cavity, the surfaces of the pin 130being accurately formed.

In the mold 131 shown in FIG. 2!, the cavity 132 has cutaway portions133 that provide projections 134 in the finished gasket. In addition,pins 135 define openings 136 in the projections 134 of the gasket.Further, the mold is provided with projections 137 that make the gasketnarrower at certain portions.

In accordance with the method and apparatus, a gasket is formed that hasaccurately formed bottom and side surfaces. The bottom surface can beformed with ribs and other configurations accurately without cutting ortrimming merely by accurately forming these configurations in the bottomsurface of the cavity of the mold.

Thus, as shown in FIG. 19, the gasket can be made so that the crosssection has spaced peripheral beads 138, 139 of different depths or asharp sealing edge 140, spaced peripheral beads 141, 142 of equal depth,a plurality of annular ribs 143, a peripheral rib 144 and an inclinedsurface 145, large peripheral beads 146, and a single peripheral bead147.

In accordance with the invention, a sealing member 150 can also be madesuch as used in car heaters. As shown in FIGS. 22, 23 and 24, a sealingmember 150 comprises a flat sheet metal body 151 having a downwardlyturned peripheral flange or edge 152 over which a gasket head isprovided.

In accordance with the invention, a mold 153 has a cavity 154 accuratelyformed in one surface thereof. The mold is provided with projections 155which engage dimples 156 in the sheet metal member 151 to locate thesheet metal member relative to the mold 153 so that the edge 152projects downwardly into the cavity 154 in spaced relation to the bottomand side surfaces of the cavity 154. Uncured vinyl plastic material isthen poured into cavity 154 in a predetermined quantity and the materialis cured in situ so that it becomes bonded to the edge 152 and defines agasket thereon which has bottom and side surfaces that are accuratelyformed.

Referring to FIG. 25, a sealing member 160 can also be made inaccordance with the invention. Sealing memher 160 comprises arectangular sheet metal body 161 having a curved flange 162 along oneside and an offset flange 163 on the other three sides thereof. A gasket164 surrounds the edge of flange 163. Sealing member 160 is made bypositioning the body 161 on a mold 165 having a cavity 166 in onesurface thereof into which the flange 163 extends. As shown in FIG. 27,the bottom 167 and side surfaces 168 of the cavity 166 are accuratelyformed so that when the body 161 rests on the surface of the cavity, theperipheral flange 163 extends into the cavity and is suspended therein.The mold 165 is formed with a cutaway portion 169 in the surface thereofand the curved flange 162 engages one edge 170 thereof to accuratelycenter and locate the body 161 therein. When the predetermined quantityof an uncured vinyl plastic material is introduced in the cavity 166 andthe material is cured in situ, it becomes bonded to the edge 163 andforms an integral gasket 164 on the sealing member 160.

The vinyl plastic compositions which are used in the invention may be ofvarious types, such as vinyl chlorides and vinyl copolymers of eitherthe dense or foam variety.

Example I A vinyl plastic foam or sponge composition which producessatisfactory results has the following composition in parts by weight:

Copolymer vinyl resin 100.0 Vinyl stabilizer 1.0 CaO 1.0 Solvatingdepressant 4.0 Polymeric plasticisers 60.0 Monomeric plasticizers 250.0Color 1.0

Example II Another vinyl plastic sponge composition which producessatisfactory results has the following composition in parts by weight:

Parts Resin Stabilizer 2 Plasticizer 50 CaO l Plasticizer 60 Wettingagent 4 Softener 10 Blowing agent 2.5

Example III A soft dense vinyl composition which produces satisfactoryresults has the following composition in parts by weight:

It can thus be seen that there has been provided a novel method formaking a novel sealing member.

I claim:

1. The method of making a sealing member having a sheet metal body witha portion embedded in a resilient plastic body that has accuratelyformed sealing surfaces which are accurately positioned relative to themetal body, which comprises forming a registering surface on theunderside of said metal body on which the plastic body is to be formed,supporting the metal body at said registering surface from an area of amold which is spaced inwardly from the peripheral edge of the metal bodysuch that the portion of the metal body on which the plastic body is tobe formed extends into a cavity of the mold and is suspended in thecavity in accurately spaced relation to the bottom of the cavity and inaccurately spaced relation laterally of the cavity, introducing apredetermined quantity of uncured vinyl plastic material into saidcavity, and curing said vinyl plastic material to form a resilientplastic body on said portion of the metal body which is suspended withinsaid cavity.

2. The method of making a sealing member having a sheet metal body withan annular portion embedded in a resilient plastic body that hasaccurately formed sealing surfaces which are accurately positionedrelative to the metal body, which comprises forming an annularregistering surface on the underside of said metal body which iselevated with respect to the portion of the metal body on which theplastic body is to be formed, supporting the metal body at saidregistering surface from an annular area of a mold which is spacedradially inwardly from the peripheral edge of the metal body such thatthe annular portion of the metal body on which the plastic body is to beformed extends into an annular cavity of the mold and is suspended inthe cavity in accurately spaced relation to the bottom of the cavity andin accurately spaced relation laterally of the cavity, introducing apredetermined quantity of uncured vinyl plastic material into saidcavity, and curing said vinyl plastic material to form a resilientplastic body on said portion of the metal body which is suspended withinsaid cavity.

3. A method 0 making a scaling member as defined in claim 1 furthercomprising: forming 0 depending flange on at least 1 portion of theperiphery of the metal body to define said portion of the metal body onwhich the plastic body is to be formed such that the flange extends intothe cavity of the mold and is suspended in accurately spaced relation tothe bottom of the cavity and in accurately spaced relation laterally ofthe cavity wherein when said predetermined quantity of uncured vinylplastic material is introduced into said cavity and cured, saidresilient plastic body is formed on said flange.

4. A method of making a sealing member as defined in claim 1 furthercomprising: forming said metal body with a non-circular periphery,forming an oflset flange on the periphery of said body with a firstportion depending from the periphery and a second portion extendingoutwardly from the lower end of said first portion such that said offsetflange extends into the cavity of the mold; said cavity having a bottomsurface and side surfaces; said ofiset flange being suspended in thecavity in accurately spaced relation to the bottom surface of the cavityand in accurately spaced relation to the side surfaces of the cavitywherein said predetermined quantity of uncured vinyl plastic material ispoured into said cavity to cover the upper and lower surfaces of saidsecond portion of said oflset flange wherein said vinyl plastic materialwhen cured forms a resilient plastic body bonded to said second portionof said flange and having surfaces accurately located with respect tosaid metal body 5. The method of making a sealing member as claimed inclaim 4 further comprising: pouring said plastic material to a depthsufficient to contact at least a portion of said first portion of saidofiset flange, and curing said plastic material to bond it to saidportion of said of first portion of said flange.

6. A method of making a sealing body as defined in claim 1 furthercomprising: forming said metal body with a nomcircular periphery;forming a downwardly turned flange on the peripheral edge of said metalbody such that said flange defines the portion of the metal body onwhich the plastic body is to be formed and is suspended in the cavity inaccurately spaced relation to the bottom of the cavity and in accuratelyspaced relation laterally of the cavity such that when the vinyl plasticmaterial is introduced into said cavity and cured in situ, said vinylplastic material becomes bonded to said flange and defines a gasketthereon which has bottom and side surfaces that are accurately formed.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the original patent.

UNITED STATES PATENTS 2,142,230 1/ 1930 Yancey. 2,358,259 9/1944Siedschlag et al. 264-275 X 2,573,225 10/1951 Seamark 277235 2,599,7676/1952 Long 277235 2,658,238 11/1953 Rizzo 18-36 2,676,823 4/1954 Olsonet a1 264294 X 2,701,894 2/1955 Hammerly et a1. 264-299 X 2,718,6649/1955 Schweitzer 264-26l 2,736,067 2/1956 Boschi 264-261 2,796,635 6/1957 Harvender. 2,893,058 7/1959 Wurtz 18-36 X 2,949,635 8/1960 Chiero18-36 3,063,097 11/1962 Jutzr 1836 3,258,831 7/1966 Angela 264-275 XR3,297,800 1/1967 Bradley 264275 XR FOREIGN PATENTS 1,175,881 11/1958France.

ROBERT F. WHITE, Primary Examiner RICHARD R. KUCIA, Assistant ExaminerUS. Cl. X.R. 26427S

